Vapor generator



a? R. H. COLLINGHAM VAPOR GENERATOR Flled June 30, 1925 [Lg/Z. His Arlorneg Inventor. Rober'r Hugh Oollingham.

Patented May 10, 1927.

UNITED- STATES! v rezasai ear EN or-Fic E.

RoBER'r HUGH GOLLINGHAM, or RUGBY, ENGLAND, ASSIGNOR T GENERAL ELEcrRIc' 1 COMPANY, A coRroRAtrIoN'oENEW YORK.

VAPOR GENERATOR;

Application filed'June 80, 1925, Serial No.

This invention relates to improvements in vapor generators, and more particularly tothe type of generator in which mercury is evaporated in revolvingtubes'.

The object ofthe invention is to provide a sealing device-for such revolving tubes to prevent the-leakage of mercury vapor. It is desirable in this type of generator to provide "sealing: devices'in which the frictional losses'between the stationary and rotating parts of the-seals are'reduced to as low value as possible, and to attain this, the present invention comprises providing each end of thdIOtfltiDo; tube with a number of impellers rotating in'separate compartments which create a pressure, which pressure counterbalances' the static head of the fluid mercury which formsthe operating fluid of the sealing devices.

The invention further comprises details of construction hereinafter described.

The accompanying drawing, Fig. 1, illustrates one method of carrying this invention into efl ect, and illustrates asingletub'eoii' a boiler ofthe type above described, the ends of the tube'being shown in section, and Fig. 2 is a'detail sectional view ona large scale of certain parts shown in Fig- 1. p

In the drawing, 1 represents a tubewhich is adapted to be supplied with mercury, and toberotated by any suitable means. at asuitable speed. This tube is provided with end connections 2 and 3, which communicate witlrthe interior of thetubeandrotate with it, the fluid mercury being led in through tl 1e:connection 2,, and the vapor generated being led away through the'rotating. connecti011j3. The 'tubfe is sup'port ed on ball or rollei bear-in'gs i," which are suitably. sups ported from the-generatorcasing. -5 are casings for the; sealing device arranged at each end" of the tube 1, and contain dia- 1iragm's 61-whic11 divide the interior of the casings into compartments ing-which rotate members 7 secured l to the *rotating connections 2 and 3. These members 7 are provided with'vanes on one si'de." On the rotating connections 2 and 3 are secured collars-8 which are engaged by carbon rings9 carried byfl \ible-- metallic bellows 10, p which are supported fro'm'the casing-51" The elasticity of the metal "bellows provide the necessary forceto' hold thecarbonfrings 9 in contact with the rotating collars 8.

Mounted on the rotating connections cumulates in the traps may be, from timerto 40,674, and in Great Britain'J'uly 2,1924.

tween the impellers a diaphragm 12 is pro vided; The casingsare also provided with end covers 13 and 1 cover 14: being fitted with a pipe 15 which leads the mercury vapor generated in the tube to a turbine or other suitable device in which it can-be utilized. The other cover 13 is provided with a pipe 16 through which fluid mercury is fed into the rotating tube from the sump of avapor condenser 17, it being understood that this may be the condenser for a turbine to which the boiler supplies operating vapor. Pipes 18 and 19 communicate withthe interior ofthe casings 5 of the sealing devices, and are provided with mercury traps 20 and 21 fitted with baffles 22.- Traps 20 and 21 are provided with drain connections 20 and 21, through whiclrthe mercury whichac time, d1 awn ofi'. Drain connections 20 and; 21 may lead to any suitable point.

When running under normal conditions, the difference in level of the mercury indicated at 28 is-equal to the vacuum in inches of the mercury held in the condenser. A pipe 24 feeds-mercury from the sump of the condenser 17 to the space 25 between the walls of the diaphragm 12 and from this into the compartmentsin which the impellers-7 and ll are rotating. c

In operation, when the tube 1 is rotating at a suitable speed, theimpellers'7 build "up; a-pressure inthe compartments-'5 in which they rotate, the total of which: pressure ba-l' ancesthe static head of-the --fiuid: mercury fed by the pipes 16 and-2 L to-th-e sealing, devices. A's a result, a mercury seal will be established," little if any mercury finding, its way'througlr the seals to pipes '18 and -19 wherethey connect to casings The-impeller 11 is'especially provided. at the seal situated at the end of the-rotating tube 1, from which vapor is led by the'pipe 15, in order to prevent the possibilityiof the flow of any liquid mercury through thepipef-lti, along with themercury vapor. The summation of the pressure of the mercury vapor and the pressure'dueto the impeller 11, balance's thestatic head of the 'condensed'mer-= themercury in the t 2 ps end 531 nod the Uslnipet'l eenlinoj pipe is sullicicut to prerent this. The l l'tfifitllt ditl'erence tlt'l'HHh the cnrbon rings Pu D it; negligible and the power expended in overcoming l'riction be tween the carbon rii and the rotating; collars in due entirely to the extension of the metallic bellows. The wcznx therct'ore, on the carbon rings nt the epeedo usually employed on such boilers is very smell, and gives it long life o the enrbon ringgo.

If, 't'or un reesou, the tube l ehould reuse to rotute, then owing to the spacing of the imliellers the mercun standing in the pipes 16 and 2t und in the sump ot the condenser would be dim-han thrtnurh the centrit'in gal settling devices into the n'lercury traps 20 end 21. The vopor nlso under pressure in the tube 1. would discharge buck through the centritturul settling devices and would exert its pressure to hold the urbon rings tightly againstthe collars, at the some time forcing its way through the mercury contnined in the traps end 2L and returning by menus ot' the pipe-i l8 and t9 ban-l; to the condenser. where the vapor would be condcnscd. There will. therefore be no appreciable leakage of mercury due to the tubes being Ft'OPPOtl tlOHl on un'loreseen rouse.

Although I hurc des ribed and illnstruted one purticulur form o'l my invention, ll do not wish to limit n'iyrelt to this particular design, us in place of a single corhon sealing ring at ouch end of the tube, l might provide u plnrnlity of rings. and n f iltlltllllly oi metallic bellows at each end ot the tube.

Also. although l hove shown onl one tube ot the hoileiu it will he understood. thut a complete boiler may comprise uny suitiuhle number of tubes.

In :n-crmlunce with the provisions of the potent; stututes, l, have d ribcd the prin ciple of operation oi. my invention, together with the uppurulus which I now consider to retn'eecnt; the best tnnbodiment thereof, but I desire to have it: understood that the up aurnt'ns shown only illustrative and that the invention may be curried out by other menus.

lVhnt I claim as new and desire to secure bylLetters Patent of the United States, is z- 1. The combination with u vapor genorator eon'lprising o. support; and a tube r0- newsroom ntttbly mom'itcrl thercim old rculinn meune to on end of the tube cinnprieing n cosine, impeller means curried hr the tube inside the casino. :1 liquid chamber lorutetl ubove the tube, snid chnmhcrbeing: adopted to contain 2t supply ol' liquid, and conduits coni'icctintt the chumhcr :it points uhor and below the level ot' the liquid in the chamber to the ens-int; zit opposite eitlcs ot -uid in! pollcr merino, the ct'nnlnitx conncctain g the curing with the chumber below the level ol' the liquid being in communication with the inter or of the tube.

:34 The wmhinntiou with :1 \upor gencrzitor compriniug :1 support u tube rotnt1- nbl mounted thereirn u condenser chumltcr locuted ztbore the tube untl adapted to contn n :1 supply of liquid, u conduit connectii'ic the chznnljitn to the tube through which liquid -upplitul to the tube, and u com'luit ctnmected to the tube for conveying vapor theretronn ol settl ng); means: for on end of the tube comprising: :1 coming, impellermoans curried hr the tube inside the casing} a conduit connccthn: the condenser chamber be low the liquid level herein with the casing to rot up :1 ntzitic head in the letter, snid im' pellet mean-2 being adopted to build up prest-ure in opposition to the static head in said roi'ulenecr clnnnber, and n pipe connecting the lower inwsure side ol" said impeller to the condenser chamber nborc the level ot the liquid therein. i

3. The CtIill'll'JlIltltlOll with n \"npor generattor comprising a support, :1 tube rotntubty mounted therein, a eonilenser chamber loeoted above the tube and adopted to contuin :1 supply of liquid, :1 conduit connecting the chamber to the tube through which liquid is supplied to the tube and no conduit; connected to the tube 'tor conveying vapor therefrom ot sealing means to amend oil? the tube comprising n cussing, impeller means carried by the tube inside the cosine, at conduit; connccting the condenser chamber below the liquid level therein with the casing to set up a static liquid head in the letter, said impeller being adopted to lntildingup u pressure in oppoeition :to the etotsic head in said supply chumher, a pipe connecting; the lower pressure side ot said impeller to the condenser chamber above the level ot' the liquid therein, and u scaling, ring tor the tube located between the casing and the tube. i i

l. The combination with urupor genera tor COITIPIlSlHQ; it support, :1 tube rotnt-ubly mounted therein and n conduit through which vapor gcneratedin the tube is Withdrown, of a sealing means for the tube co1nprising a casing, two spaced impeller means carried by the tube inside the casing, u liquid chamber located above the tube, said chamber being adapted to contain a supply of liquid, 21 pipe connecting the lower end of the liquid chamber to the spaeebetween said impeller means, the casing being adapted to pro vide a space adjacent the outer end of one of said impeller means which is in communication with the first-named conduit, and a space adjacent the outer'end of the other impeller means, and conduit means connecting the last-named space with the liquid chamber above the liquid level.

5. In a vapor generator of the rotating tube type, the combination of a support, a tube having open ends rotatab'ly mounted therein casings surrounding the ends of the tube whereby saidcasin'gs are in communication with and connected by said tube, a conduit for supplying liquid to each of said casings, a conduit for conveying vapor from one of said casings, a liquid chamber with which the supply conduits connect, said chamber being adapted to set up through said connectionsastatic pressure in the casings, a packing means for the tube end in each casing comprising a yieldingly pressed sealing ring supported from the casing and a collar carried by the tube against which the ring packs, and impeller means mounted on the tube ends in said casings for building up pressures to counterbalance the static pressure of the liquid from said chamber.

6. The combination with a vapor generator comprising a vaporizing tube and a supporting means in which said tube is rotatably mounted, of means for conducting a liquid to be vaporized through said tube, comprising tubular open end members forming axial extensions of the, tube, casings carried by the supporting means into which said members project, means including a conduit connected with each casing for supplying liquid thereto Lmder pressure, one of said conduits terminating adjacent the open end of one of the tubular members whereby it is operate to create pressure in opposition to the liquid pressure therein, and a second impeller means located in the casing with which the outlet conduit is connected, said impeller means being located between the outlet conduit connection with said casing and the supply conduit connection with said casin 7. The combination with a vapor generator comprising a vaporizing tube adapted to provide a conduit for a liquid to be vaporized, and a supporting means in which said tube is mounted to rotate about its longitudinal axis, of a pair of tubular end connections for the tube, said end connections having open outer ends and being connected with the tube to rotate coaxially therewith, and sealing means for the end connections comprising casings into which said end connections project, a packing device in each casing surrounding the end connectiontherein and forming a'closure for one end of each casing, an end cover forming a closure for the opposite end of each casing, a rotary liquid sealing device in each casing between the end cover and the packing device having impellers which rotate with the end connections to balance a static liquid pressure in each casing and means connected with each casing for supplying a liquid thereto under static pressure.

In witness whereof, I have hereunto set my hand this 10th day of June 1925.

ROBERT HUGH COLLINGHAM; 

